1. Field of the Invention
The present invention relates to a playback apparatus and a playback method that plays back multi-viewpoint video data or arbitrary viewpoint video data.
2. Description of the Related Art
Televisions (digital television apparatuses) that are capable of receiving digital broadcasts have become popular. Currently, in the age of full-fledged digital broadcast, research and development on various next-generation broadcast systems have been carried out. Among them, display technologies of a “plural viewpoint video” (e.g., multi-viewpoint video), by which a viewer can select a viewpoint from a plurality of camera viewpoints, or display technologies of an “arbitrary viewpoint video”, by which a viewer can arbitrarily provides instructions about the viewpoint, have received attention. Japanese Patent Laid-Open No. 2007-150747 discloses an apparatus that receives a broadcast stream including a broadcasting video and the viewpoint information about the video. When a distribution request for an arbitrary viewpoint video is made, this apparatus utilizes the viewpoint information extracted from the broadcast stream as the viewpoint initial value for the arbitrary viewpoint video.
As a next-generation digital broadcast service, the provision of a multi-viewpoint video or an arbitrary viewpoint video is further expected to become popular. In a next-generation record/playback apparatus, an apparatus that can record/playback data for a multi-viewpoint video or an arbitrary viewpoint video is desired.
In the playback apparatus for a plural viewpoint video or an arbitrary viewpoint video, assume the case in which video data is played back and then resumed after an interruption period. If a viewer views another program or content during the interruption period, the following situation may occur. For example, a viewer may forget the fact that the program played back after interruption is a multi-viewpoint video program or may misunderstand the fact that the playback screen of a multi-viewpoint video is the viewpoint of a normal broadcast program and keep viewing the playback screen. As a result, there is a possibility that a viewer may miss the opportunity of viewing a normal broadcast or the other multi-viewpoint video, and thus may not effectively utilize a multi-viewpoint video broadcast service. In addition, some viewpoints may cause a viewer to be unable to grasp the entire state. Furthermore, as the interruption period is extended, the entire flow of a program and a temporal before-and-after relationship may become unclear.
Accordingly, the present invention provides a playback apparatus and a playback method that are capable of playing back video from an appropriate viewpoint upon the resumption of the playback of plural viewpoint video content or arbitrary viewpoint video content after the playback thereof is stopped.